This invention relates to a belt conveying apparatus and an image forming apparatus having a cleaning apparatus for cleaning a surface of a transfer belt of a transfer portion for transferring a toner image.
Recently, a color image forming apparatus such as a color copier has been developed according to colorization of office documents or the like. Further, there is known a four-drum-type image forming apparatus which includes four photosensitive drums (as image bearing bodies) arranged parallel to each other. Such an image forming apparatus is configured to form toner images on the respective photosensitive drums using toners (as developers) of, for example, yellow, magenta, cyan and black. The respective toner images are transferred to a sheet conveyed by a transfer belt (an endless belt) of a transfer portion so that toner images of respective colors are superimposed with each other. Conventionally, the transfer portion of the image forming apparatus has a cleaning blade formed of urethane rubber or the like for removing a toner adhering to a surface of the transfer belt. Such a conventional image forming apparatus is disclosed in, for example, Japanese Laid-Open Patent Publication No. 2004-77607 (paragraphs 0025-0033 and FIG. 10).